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The "cash for clunkers" program was a limited federal government program in the U.S. that gave people credits to trade in their old, gas guzzling, polluting cars for newer ones. The goal was to get older cars off the road to improve pollution. Because the “cash for clunkers” program did not allow the re-sale of old car engines, junkyards were forced to turn the cars into scrap metal. Listen to learn what this scrap metal can be turned into.
Hydraulic fracturing or fracking is the process of putting liquid into shale to remove natural gas. There's concern that when the drillers get rid of wastewater from fracking, it goes into the ground and causes earthquakes. This is happening in places such as Arkansas, and now residents are speaking up to try to put a stop to it. Listen to learn how residents figured out where the earthquakes were coming from and how they are taking the issue to court.
Human beings have a long-standing fascination with dinosaurs that dates back to the discovery of the first fossils. To this day, people of all ages visit museums and fossil sites to study and learn more about these prehistoric creatures. This audio story features the answer to a seemingly simple question: how did the dinosaur age begin? Listen to hear what scientists know about the beginning of the age of dinosaurs. The story may contain a few surprises!
As the ocean rises, some island nations might disappear and the coastlines change. This is critical for some island nations that are at risk of slipping under water as sea levels rise. Political, economic, and personal consequences are factors in how the climate problems in these nations are dealt with. Listen to learn what can be done to prevent these catastrophic changes in our geography.
North American river otters have adapted both physically and behaviorally to survive the long, cold winters of North America. This episode of Earth Rangers features an interview with a conservation zoologist about how the river otter’s physical features, behaviors, and social structures help it find the shelter and food it needs to survive, with a particular focus on the important relationship between river otters and beavers. Listen to hear about the physical and behavioral adaptations that help North American river otters thrive.
Oceans are home to millions of sea creatures, but not everyone is lucky enough to be able to take a trip to the ocean to see these creatures up close. This is where aquariums come in. Aquariums allow people to connect with nature and learn about many different species of ocean animals. But aquariums may not always be the best place for those animals to live. Listen to the president of Baltimore’s National Aquarium discuss some of the amazing animals in his care and the challenges of providing them with everything they need.
Can humans and wildlife coexist peacefully? Local farmers in Malawi have witnessed how living near wild elephants can result in violent human-animal encounters. Poachers feed on these circumstances and seize the opportunity to profit. An artificial intelligence solution called EarthRanger has been introduced that can protect the local communities and elephants and bring poachers to justice. Listen to discover how this life-changing solution has impacted elephants and farmers alike.
Most people don’t like to spend time thinking about snot, slime, and mucus. Believe it or not, these are important substances that keep humans and animals safe. In fact, there are scientists who study snot! Listen to hear one of these scientists talk about what snot is made of, which animals produce the most slime, and how humans and animals use snot and slime to stay safe and healthy.
Does tickling have a purpose? Why are certain parts of the human body especially sensitive to tickling? Scientists believe the tickling response evolved in early humans to help them protect themselves from predators and insects. Tickling also gives scientists clues about how the brain signals other parts of the body to respond. Listen to hear more about the protective response of tickling, and learn why it is impossible to tickle yourself.
Animals use their whiskers for more than just looking cute. This audio story features an interview with a scientist who studies how whiskers are used by different animals. Listen to hear how animals use whiskers to learn about the world around them and about an experiment that helps scientists learn how whiskers work.
Small green sea slugs puzzle scientists because they can photosynthesize energy, just like plants. These Eastern Emerald Elysia sea slugs also appear to have several different types of DNA. Scientists are hopeful these sea slugs might help them discover more about human DNA and treat human diseases. Listen to learn how these tiny creatures are teaching us more about genetics.
Are humans alone in the universe? This question has endured since people first looked to the heavens. NASA is getting closer than ever before to answering that question. Thousands of planets outside of our solar system have already been discovered, and a recently launched NASA satellite called TESS may discover even more. Will any of the thousands of newly discovered exoplanets be like Earth, able to sustain life? Listen to this story to learn how NASA is searching for Earth’s twin.
The bowhead whale lives its entire life - which amazingly can span over 200 years - in the frigid Arctic waters near the North Pole. The bowhead whale is unlike most other whales as it doesn’t seasonally migrate in search of warmer waters. A thick layer of blubber and the ability to hold its breath for up to 30 minutes makes it possible for bowhead whales to live in the deep, freezing water. Listen to hear even more incredible facts about this unique ocean mammal.
As plants and animals reproduce over time, they are able to change and adapt to ensure or improve their chances of survival. The evolutionary goal of reproduction is paired with the concept of natural selection and survival of the fittest to determine who will reproduce. From colorful plumage to size, different species use different strategies to ensure reproduction and mate selection. The sand tiger shark has a unique strategy to ensure successful reproduction - and it depends on the timing of mating. Listen to learn more about the ultimate sibling rivalry while in the womb.
The increasing acidity of the oceans could eventually affect your dinner plate. There is a decrease in the number of juvenile oysters known as "seed" due to the increase of CO2 in the ocean. Listen to learn how workers are dealing with the issues and how it affects the seafood we eat.
Wolverines are fierce predators and scavengers that live in the remote forests near the Arctic Circle. As these solitary animals need at least 500 square kilometers of space each and can travel vast distances each day, they are very difficult to spot in the wild. Wolverines play an important role in the ecosystem as they scavenge the carrion left behind by other predators. Listen to hear more about this elusive mammal, including why people walking through the forest shouldn’t worry about being attacked by one.
Imagine a large asteroid on a collision course with Earth. How would scientists know, and what could they do about it? An international group of scientists, engineers, and emergency managers recently held a planetary defense exercise, including the simulation of an asteroid predicted to hit near Denver, Colorado. Listen to learn more about how these experts plan to defend Earth from devastating impacts, and how they might respond if those defenses fail.
The apples we are used to seeing in the supermarket are the same basic size and shape and they have familiar flavor profiles. But there are more apple varieties than you might imagine. There's a whole world of biodiversity in apples, but these apples don’t make it to the supermarket. Listen to learn more about America’s history with apples and the apple Renaissance taking place today!
To lower dependency on fossil fuels, some Americans have installed solar panels on their homes to produce their own clean energy. This decision involves a cost-benefit analysis of cost value and environmental impact. In some regions this cost-benefit ratio has been upset by fracking, and the cheap natural gas that it produces. How does supply and demand impact the cost of energy? How does the cost of energy impact people seeking alternatives such as solar energy? Listen to learn how one family has dealt is dealing with this shifting energy landscape.
Pets are an important part of many people’s lives. Different types of animals have different needs, and some are more difficult to care for than others. It is important that pet owners know the appropriate way to care for their pet to ensure they are living a healthy and well-balanced life. Listen to an interview with a veterinarian as he talks about his passion for animals, answers questions about pet care, and discusses how he feels the COVID-19 pandemic has affected the animals living in people's homes.
Tsunamis are created by tectonic plates thrusting against each other and then lifting the sea floor and dropping it down, which creates a giant wave. A 2010 earthquake in Chile was caused by a shift in the seafloor. This same shift set off tsunami detection buoys and left scientists waiting for the tsunami to hit. But it ended up being small. Listen to learn more about this quake and how tsunamis are created.
When people started using large nets to capture tuna in the 1960s, many spotted dolphins were killed because they were found living with tuna. Scientists responded by sending “observers” on tuna boats to keep track of the number of dolphins killed. Listen to hear from a scientist who is studying the spotted and spinner dolphins to try to learn how to preserve dolphin populations.
Scientists are creating bacteria batteries by using wastewater to generate electricity. The microbes from sewage can be harnessed to develop microbial fuel cells. The process could provide ways to provide energy in remote places for very little money. Listen to learn how scientists are developing this energy and what they are learning from it.
One of the biggest earthquakes ever recorded struck recently, with minimal damage, no tsunami and it barely made the news. That’s because there are two kinds of earthquakes. This earthquake happened when two tectonic plates moved past each other horizontally, while more damaging earthquakes are caused when one plate slips beneath another. This radio story explains the two types of earthquakes and how they are gradually redefining the boundaries of the tectonic plates.
A new threat to human health, a disease called COVID-19, is spreading rapidly around the globe. The cause of COVID-19 is a coronavirus, named for the crown-like spikes on the surface of the virus particles. In this audio story, an infectious disease doctor describes COVID-19 and its symptoms, compares the novel (or new) coronavirus to the better-known coronavirus that causes the common cold, and explains why being novel helps the virus to spread. Listen to learn what scientists want people to do in order to slow the spread of the novel coronavirus and protect the health of individuals, families, and communities.
Global warming is expected to increase summer temperatures making cities even hotter. As concrete and asphalt within cities retain heat, it can increase health risks. The sun mixes with city pollution to create ozone that can irritate people's lungs, especially if they have breathing problems such as asthma. Listen to learn how public health officials are trying to help those living in the hottest areas.
Game wardens in California are now using DNA fingerprinting analysis to help protect illegal poaching of wildlife. There are many species, from large game to shellfish, which are being illegally caught or killed for food. Since there are so few game wardens to patrol the state, they are relying on forensic evidence to help track poachers. Listen to learn about the latest in DNA fingerprinting technology.
Alaska is home to 54 active volcanoes. Scientists, called volcanologists, watch and study these volcanoes to try and predict when they are going to erupt and so they can give warnings to the nearby communities. In 2008, Mount Redoubt, one of Alaska’s most famous volcanoes that is known to be active and dangerous, began to show signs of erupting. Listen as a volcanologist explains how taking a closer look at what goes on deep down below the surface of a volcano like Mount Redoubt can reveal warning signs that indicate a possible eruption.
As nations look for clean energy alternatives, many are turning to wind and solar, but Indonesia is turning to its volcanoes. Indonesia has 130 active volcanoes. These volcanoes generate geothermal heat that is released through vents and hot springs throughout the country. Power companies are learning to harness and redirect this heated steam into power plants in order to generate electricity. Indonesia’s geothermal energy potential is huge, but start up costs and oil subsidies might prevent this burgeoning clean energy from taking off.
A whale inhales and exhales air through the blowhole at the top of its head. The plume that rises when the whale exhales is made up of blow, a scientific term for whale snot. Whale snot can reveal important information about whale stress, but collecting the snot can be challenging. Listen to hear a scientist describe how she collects whale snot and what it can tell us about how whales are coping with the effects of climate change.
It's easy for some people to imagine what it's like to be a doctor, lawyer, or teacher. However, the day-to-day life of a shellfish and wetland ecologist can be a little more difficult to understand. Discover what an ecologist does by hearing from Danielle Kreeger, the science director for a group that works to protect and improve the Delaware River and Bay. Listen to hear more about her career as an ecologist.
What is electricity? How does it work? Where does it come from? Everyone has heard of electricity, but most people don’t understand much about it. Scientists have studied electricity for centuries, and they still have many unanswered questions! Listen to an electrical engineer explain some of the things we know, and still don’t know, about electricity.
All animals, including humans, need to sleep. Scientists have several theories that help explain why we sleep. In this episode of But Why, a child sleep psychologist describes the evolutionary theory of sleep and explains how sleep benefits the brain and body. Listen to learn more about the science of sleep and its importance for healthy growth and development.
Woolly mammoths were large, elephant-like creatures that lived tens of thousands of years ago, during the last great ice age. The thick, furry coat is one of several traits that gave woolly mammoths an advantage in a very cold environment. Today, the closest biological relative is the Asian elephant, which prefers warmer climates. Scientists were curious about the genetic variations between the woolly mammoth and the Asian elephant, and what might account for the differences between the two species. In this audio story, we hear from a scientist who studied the DNA from the extinct mammoth and compared it to its contemporary descendant. Listen to learn more about what researchers discovered.
Wildlife in the city? It may seem odd to hear the word “wildlife” linked to the word “city.” However, animals live wherever they can find food and shelter. Cities can provide both for many types of wildlife. Animals use their survival skills to turn just about any environment into their home. Listen to hear a scientist explain which animals can be found in suburbs and cities and how they adapt to these environments.
Wolves often get a bad rap, especially in fairytales. But are they really as bad as they seem? Yes, wolves are top predators, but there is much more to these awesome animals than simply their hunting habits. Listen to an expert explain fascinating details about wolves, from the complexity of their packs to how the dogs and wolves of today stem from the same extinct species.